Low power remote switch device

ABSTRACT

A circuit having low voltage and low current means for controlling higher voltages, higher currents, and higher power circuits. The circuit comprises solid state devices but is not limited to solid state devices. The circuit may be closed by low voltage contacts while maintaining isolation from higher voltages and currents.

United States Patent n 1 Asija May 27, 1975 LOW POWER REMOTE SWITCH DEVICE [76] Inventor: Satya Pal Asija, 164i Cumberland St. Apt. 2|. St. Paul, Minn 55117 122 Filed: Oct.23, I973 211 Appl. No.: 408,663

Related U.S. Application Data [63] Substitute for Ser. No. 804,052, Feb. 27, 196

abandonedv [52] US. CL 307/116; 340/279 [51] Int. Cl. H03k 17/00 [58] Field of Search 307/252 B, 252 N, 308, 307/116; 340/279; 200/86, 1

[56] References Cited UNITED STATES PATENTS 766,17] 8/l904 Crosby et al 340/279 Atkins 340/279 X Teskc 307/252 B Primary ExaminerHerman J. Hohauser [57 ABSTRACT A circuit having low voltage and low current means for controlling higher voltages. higher currents, and higher power circuits. The circuit comprises solid state devices but is not limited to solid state devices. The circuit may be closed by low voltage contacts while maintaining isolation from higher voltages and currents.

3 Claims, 4 Drawing Figures LOW POWER REMOTE SWITCH DEVICE RELATED APPLICATION This patent application is a substitute for application Ser. No. 804,052, filed Feb. 27, 1969, now abandoned.

BACKGROUND OF THE INVENTION It is frequently desirable to have available a low voltage switch device, which is capable of controlling higher voltages and currents. However, known devices for such use have moving parts such as a relay, or arcing devices or transformers.

It is an object of this invention to provide a low voltage switch device which is capable of controlling higher voltages and currents, but which does not include, a transformer, a relay, or an arcing switch, or any other moving part.

Another object of this invention is to provide such a device which may include exposed or uninsulated wires in its control circuitry.

Another object of this invention is to provide such a device which may be constructed at a relatively low cost.

Another object of this invention is to provide such a device which may be used for multiple applications, for example, for de-energizing an electrical appliance as a person falls asleep, as an aid to crime detection, precision use of an electric drill in drilling holes, for remote control of television commercial deenergizer, audible continuity tester, lawn sprinkler control, fire alarm, press-to-talk switch for tape recorders, headlight garage door opener and the like.

It is an object of this invention to provide such a switch device, which does not require conventional terminals, contacts and the likev Other objects and advantages may reside in the construction of the device and the combinations therein, as may be apparent from the following description.

This invention is a low power remote switch device, comprising a low voltage, low current control circuit, with means to control higher voltages and higher currents, which includes but it is not limited to:

a. means for impressing power,

b. means for connecting to various electrical appliances and c. a plurality of control wires, with means for making available any or all parts of the impressed power to an electrical appliance connected to this device.

The control circuit further employs but is not limited a. a bi-directional silicon controlled rectifier in series with an input plug and an output receptacle,

b. a transistor in series with the gate of the bidirectional silicon controlled rectifier,

c. two do batteries, one for biasing the base emitter junction and another for biasing the gate of the bidirectional silicon controlled rectifier through the transformer,

d. a plurality of exposed wires or conductors which form the means to interrupt transistor bias.

As the transistor bias is interrupted, the transistor be comes non-conducting, thereby removing bias from the gate of the bidirectional silicon controlled rectifier, which, in turn, deenergizes the power impressed at the input plug.

BASIC DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic diagram of the preferred embodiment of the low power remote switch device of this invention.

FIG. 2 is a perspective view of the invention, the low power remote switch device, with input, output and control wires.

FIG. 3 is an electrical circuit diagram of a modification of the invention.

FIG. 4 illustrates use of the device as an aid to crime detection.

DESCRIPTION OF THE PREFERRED EMBODIMENT A switch device of this invention is a low power remote control device comprising, as shown in FIG. 1, an input plug 12, with prongs l4 and 16, to which are connected conductors 18 and 20, respectively. In addition, the input plug 12 may have another prong 15, for grounding purposes.

The switch of this invention also includes a small voltage direct current source 22, herein shown as a bat tery, having a negative terminal 24 and a positive term inal 26, which are connected to conductors 20 and 28, respectively. An NPN transistor 30, having a collector terminal 32, base terminal 34, and an emitter terminal 36, is connected to conductors 28, 35, and 38, respectively. The conductor 35 is a control conductor and may be an uninsulated exposed wire and is a part of the low voltage, low current and consequently low power control circuit. Another small voltage direct current source, herein in the form of a battery 40 has a negative terminal 42 and a positive terminal 44, which are connected to the conductor 38 and to a conductor 45 or exposed wire 45, respectively. The conductor 45 and the conductor 35 are part of a low voltage, low current circuit and consequently are low power control circuit wires, These conductors 35 and 45 may thus be grasped in a persons hand.

The switch device of this invention also includes an output receptacle or socket 46, having recesses 48 and 50 which are connected to the conductor I8 and a conductor 52 respectively. In addition, the output socket 46 may have another recess, not shown, for grounding purposes.

Another element of the switch device of this invention is a bi-directional silicon controlled rectifier or triac 54, such as a triac or two silicon controlled rectifiers connected back-to-back in parallel, resulting in three terminals (T2) 56, a gate 58, and (T1) 60, which are connected to the conductors 52, 38, and 20, respectively. Furthermore, in order to provide good heat sink and yet retain electrical insulation from a chasis or body 64, on which the citcuit is assembled, a mica washer 62 is conventionally used, as an insulator. The ground terminal 15, if any, with the input plug 12 or ground recesses 49, if any, with the output receptacle 46 are also connected to the chasis or body 64 as a safety precaution.

In order to prolong the circuit and battery life, the electrical potential difference of the battery 40 should preferably not exceed base-to-emitter saturation voltage of the transistor 30. Therefore, a resistor 66 is used in the base 34 of the transistor 30, as shown in the mod ified embodiment of the invention in FIG. 3.

The potential of the battery 22 is dictated by the gate current of the bi-directional silicon controlled rectifier 54 and is not at all critical. The batteries 22 and 40 are preferably mounted so that easy replacement thereof is convenient.

OPERATION Connection or contact of the exposed wires 35 and 45, one with the other, may be made in the hand of a user or by a transducer or by a time switch or other type of switch device or the like. When the wires 35 and 45 are in contact, one with the other, the battery 40 forward biases the base 34 with respect to emitter 36, thereby placing the transistor 30 in conduction state and the transistor continues to be in the ON state as long as the connection between the control wires 35 and 45 is maintained. As the transistor 30 conducts, the emitter 36 approximates the potential at the collector 32, which is forced positive with respect to the conductor by virtue of the battery 22. Thus, the gate terminal 58 of the triac 54 is also positive with respect to the conductor 20 or the terminal (T1) 60 of the triac 54.

This causes the bi-directional silicon controlled rectifier or triac 54 to conduct. Accordingly, the terminals (T1) 56 and (T2) 60 are at the same potential. Thus the same power is available at the output receptacle 46 as is impressed at the input plug 12. Since the triac 54 is a bi-directional device, the circuit is operative for both half cycles of the alternating current which is supplied through the input plug 12 and is limited only by capacity of the triac 54.

Conversely when the connection or contact between the conductors 35 and 45 is broken, the transistor 30 turns off, which turns off the triac 54. This, in turn, interrupts the power at the output socket 46.

The switch device of this invention has numerous applications. For example, the switch device of this invention may be employed as a sleep sensing switch. When the device of this invention is employed as a sleep sensing switch, an electrical appliance, such as a tape recorder or a television set is connected to this device. The plug of the electrical appliance is plugged into the output socket 46 of the device. The plug 12 of the de vice of this invention is plugged into a wall socket or the like. The normal energizing switches of the appliance are placed in the ON state.

To energize the television set or the tape recorder which is connected to the socket 46, the conductors 35 and 45 are manually grasped and held in contact with each other between thumb and a finger. It has been learned that as an adult person falls asleep, the person cannot continue to manually grasp an object. Therefore, when such a person falls asleep with conductors 35 and 45 in his hand, he does not continue to maintain contact between the conductors 35 and 45. Accordingly, the appliance is de-energized quickly after the person falls asleep.

The device of this invention may also be employed as an aid to crime detection. To use this device to apprehend criminals who demand money at gun point, a bright flashing red lamp 72, as shown in FIG. 4, is plugged into the receptacle or socket 46 and mounted on the top of a building, such as a bank building 80. Thus, the red lamp 72, when lighted is readily observed. the plug 12 of the device is plugged into any convenient wall socket. The conductors 35 and 45 are located strategically throughout the building, especially around such places as teller positions, cash register, service counter, etc. If and when someone demands money at gun point or the like from a teller, the teller causes contact between conductors 35 and 45 which may be very thin concealed wires, which make no noise and are not easily observed. These exposed wires 35 and 45 may be manually contacted without danger of high voltage. Thus, the flashing red lamp 72 or other alarm, is energized as an indication that an emergency exists.

THE SWITCH DEVICE IN PRECISION DRILLING Precision hole drilling in metals is a skill which is not common or easily obtained. When the drill machine is energized through the switch device of this invention and one of the conductors 35 or 45 is connected to the drill machine bit and the other to the work piece in which precision hole is desired, the drill begins to rotate only when the operator engages the work piece at a position at which a hole is desired. It is known that it is easier to drill a hole at a desired location if the drill does not begin to rotate until the bit engages the work piece at the desired location.

AS A TV OR RADIO COMMERCIAL DE-ENERGIZER With reference to FIG. 3, which is the circuit diagram of a modification, by proper selection of variable resis' tors 66 and 68, it is possible to maintain only half power at the output receptacle 46 when the contact between conductors 35 and 45 is broken. To use it as a deenergizer for commercials, one merely interrupts contact between conductors 35 and 45 as a commercial comes on the TV screen. The power is reduced onehalf, which in turn turns the TV off, but at the same time it keeps the circuits, and even the cathode ray tube, warm. Thus, after a precalculated pause of say seconds, the TV turns on within a second or two of maintaining the contact between conductors 3S and 45. Accordingly, the user does not have to wait for the warm up time, after the commercial interruption.

The invention having thus been described, the following is claimed:

1. Apparatus for turning off an electrical appliance as a person falls asleep, which comprises a low power solid state control circuit for controlling higher power control circuit which includes:

a. conductor means including solid state means for connection to a source of electrical energy of a given voltage,

b. output means for connecting the conductor means to an electrical appliance comprising a bidirectional silicon controlled rectifier having a gate and a base, and

0. switch means including solid state means operable at less than the given voltage and joined to the conductor means for controlling flow of electrical energy to the output means, where in the switch means includes a transistor in series with the gate of the bidirectional silicon controlled rectifier, and a plurality of direct current batteries, one battery being connected to the base and one battery being connected to the gate of the bi-directional silicon controlled rectifier, the switch means also including a plurality of conductors, means connecting one conductor to one of the batteries, and means connecting another conductor to the other battery.

2. Apparatus for turning off an electrical appliance as a person falls asleep, which comprises a low power solid state control circuit for controlling higher power control circuits, which includes an input means, an output means, and a conductor means for connection between the input means and the output means, where in the low power solid state control circuit is further characterised by:

a. a bi-directional silicon controlled rectifier device, including a gate and having a plurality of terminals, one terminal being connected to the conductor means, and another terminal of the bi-directional silicon controlled rectifier being connected to the output means,

b. a transistor having a plurality of terminals, including a collector, a base, and an emitter, means connecting the emitter to the gate of the bi-directional silicon controlled rectifier,

c. a plurality of low voltage direct current sources,

each source having a plurality of terminals, including a positive and a negative terminal, means connecting one low voltage source to the emitter base junction of the transistor,

d. a plurality of control wires, one control wire being connected to the base of the transistor and one control wire being connected to one of the low voltage direct current sources.

3. An apparatus for turning off an electrical device as a person falls asleep, which comprises:

a. means responsive to a sleep threshold condition to interrupt flow of electrical energy from a source of electrical energy to an electrical device, including a plurality of exposed wires adapted to be held in a persons hand between a thumb and a finger;

b. conductor means for connecting an electrical device to a source of electrical energy;

c. switch means joined to the conductor means for interrupting flow of electrical energy from a source of electrical energy to an electrical device,

d. a bi-directional silicon controlled rectifier, includ a transistor having a plurality of terminals, including a collector, a base and emitter, means connecting the emitter to the gate of the bi-directional silicon controlled rectifier;

f. a plurality of low voltage direct current sources,

each source having a plurality of terminals, including a positive and a negative terminal, means connecting one low voltage source to the emitter base junction of the transistor; and

g. a plurality of control wires, one control wire being connected to the base of the transistor and one control wire being connected to one of the low voltage direct current sources. 0 

1. Apparatus for turning off an electrical appliance as a person falls asleep, which comprises a low power solid state control circuit for controlling higher power control circuit which includes: a. conductor means including solid state means for connection to a source of electrical energy of a given voltage; b. output means for connecting the conductor means to an electrical appliance comprising a bi-directional silicon controlled rectifier having a gate and a base; and c. switch means including solid state means operable at less than the given voltage and joined to the conductor means for controlling flow of electrical energy to the output means, where in the switch means includes a transistor in series with the gate of the bi-directional silicon controlled rectifier, and a plurality of direct current batteries, one battery being connected to the base and one battery being connected to the gate of the bi-directional silicon controlled rectifier, the switch means also including a plurality of conductors, means connecting one conductor to one of the batteries, and means connecting another conductor to the other battery.
 2. Apparatus for turning off an electrical appliance as a person falls asleep, which comprises a low power solid state control circuit for controlling higher power control circuits, which includes an input means, an output means, and a conductor means for connection between the input means and the output means, where in the low power solid state control circuit is further characterised by: a. a bi-directional silicon controlled rectifier device, including a gate and having a plurality of terminals, one terminal being connected to the conductor means, and another terminal of the bi-directional silicon controlled rectifier being connected to the output means, b. a transistor having a plurality of terminals, including a collector, a base, and an emitter, means connecting the emitter to the gate of the bi-directional silicon controlled rectifier, c. a plurality of low voltage direct current sources, each source having a plurality of terminals, including a positive and a negative terminal, means connecting one low voltage source to the emitter base junction of the transistor, d. a plurality of control wires, one control wire being connected to the base of the transistor and one control wire being connected to one of the low voltage direct current sources.
 3. An apparatus for turning off an electrical device as a person falls asleep, which comprises: a. means responsive to a sleep threshold condition to interrupt flow of electrical energy from a source of electrical energy to an electrical device, including a plurality of exposed wires adapted to be held in a person''s hand between a thumb and a finger; b. conductor means for connecting an electrical device to a source of electrical energy; c. switch means joined to the conductor means for interrupting flow of electrical energy from a source of electrical energy to an electrical device, d. a bi-directional silicon controlled rectifier, including a gate and having a plurality of terminals, one terminal being connected to the conductor means, and another terminal of the bi-directional silicon controlled rectifier being connected to the means responsive to the sleep threshold condition; e. a transistor having a plurality of terminals, including a collector, a base and emitter, means connecting the emitter to the gate of the bi-directional silicon controlled rectifier; f. a plurality of low voltage direct current sources, each source having a plurality of terminals, including a positive and a Negative terminal, means connecting one low voltage source to the emitter base junction of the transistor; and g. a plurality of control wires, one control wire being connected to the base of the transistor and one control wire being connected to one of the low voltage direct current sources. 